Dynamo-electric machine



P. BAIN. v DYNAMO ELBGTRIC MACHINE.

' Pat ted July 3, 1883. gig 6 WITNESSjES: I INVENTOR:

a; I BY t v v ATTORNEYS.

- N. PETERS, Phmmmn n mr, Washinglan. n. c.

' UNITED STATES 7 PATENT OFFICE.

Fonnn BAIN, on MINNEAPOLIS, MINNESOTA, ASSIGNOR T 'r. c. SPRINGER,

, on CHICAGO, ILLINoIs.

DYNAMO-ELECTRIC MACHINE.

SPEGIFICATION forming part of Letters Patent No. 280,708, dated July 3, 1883.

Application filed September13, 1882. (No model.) I

To all whom, it may concern:

Be it known that I, FOREE BAIN, of Min neapolis, in the county of Hennepin and State of Minnesota, have invented anew and Im- 5 proved Armature for Dynamo-Electric Machines, of which the following is a full, clear, and exact description.

My invention relates to the construction of the armature-cores of d'ynamoelectric machines, the object being to prevent residual magnetism and obtain the maximum of saturation of the armature and its quick discharge. Reference is to be had to the accompanying drawings, forming a part of this specification, 1 in which similar letters of reference indicate corresponding parts in all the figures.

Figure 1 is a side elevation of an armaturering of my improved construction. Fig. 2 is a face view of a portion of the ring before being bent to receive the wires, and Fig. 3 is a cross-section of two rings as connected to form an armature.

v In the manufacture of the cores a ring of sheet-iron is cut or stamped out in. the form shown in Fig. 2-that is, with inner and outer projecting tongues, a. a. The inner tongues are then bent outward, so as to project in the same direction as the outer tongues, and with them form polar extensions, as shown. in Fi 1, and with space betweenv the tongues for receiving the wire, as shown in Fig; 3. The core thus formed is then wound circumferentially with annealed iron wire or ribbon, as shown at c. The wires or rib 5 bons are either naked or covered with in sulating material, and are held in place by the projecting tongues at each side. This ring with its polar extensions and winding of wire constitutes the core of the armature; or two or more of them may be attachedtogether side by side, as shown in Fig. 3, strung on pods (1,, passing through the outer ends of the polar extensions, and separated by wash ers e, of insulating material. The core thus 5 made, or before the rings are attached together, is preferably to be covered or coated with porcelain, glass, or any insulating material of a vitreous nature which is. a poor conductor of heat, so as to form a completely insulated surface on which to wind the conductor. The conducting-wire is wound upon the core in the usual manner, as shown at f, Fig. 1.

By this construction of armature residual magnetism is avoided, the armature will read- 5 5 ily attain the maximum of saturation and yield quickly tov changing influences, and as it rotates in close proximity to the field-magnets by virtue of the polar extensions it thereby cuts a more intense magnetic field than those fields of force in which armatures are not provided with polar proj ections.v

By constructing the frame or sheet-metal ring with a notched periphery, or one having a series of separated tongues, I also attain an important result in respect to economy or cost of manufacture, and also reduce to a minimum both the weight of the armature as a whole and the power required to drive it at the required speed. '70

I am aware that it is not new to use a U- shaped iron core formed of wire wound about a guard of sheet-iron, and about this insulated conducting-wires; but

hat I claim as new and of my invention 7 5 1. A method of forming an ar1nature-core, which consists, first, in cutting out of sheet metal a ring with inner and outer tongues; secondly, bending the inner tongues until they are brought opposite the outer ones thirdly,

applying a vitreous coat to the outer surface;

and, fourthly, winding between the tongues annealed iron wire, all substantially as described. 2. An armature-core formedofa sheet-metal ring provided with a vitreous surface coat, and having outwardly-extending oppositetongues with annealed iron wire between them, as described. 0 3. The improved armature-core composed of the circular skeleton-frame or ring formed of a plate of sheet .metal having a series of separated tongues, a, on each sidefand which are bent intoradial position, as shown, and a 5 layer of iron wire wound circumferentially in the space between said tongues, as herein wire 0 is laid. circumferentially, each of the specified. rods passing through a pair of such tongues 4. The combination of the rods (1 and wash on each ring or core, as shown and described.

ers c with two or more circular armature FOREE BATN. 5 cores, each formed of a sheet-metal plate bent \Vitnesses:

into ring shape, and having series of radially- R. S. BATES,

separated tongues, a, between which the iron N. F. HAWLEY. 

